| high pressure sodium.
A neighbour of mines 600 watt 240 volt HPS lamp accidentaly grounded out. A chain was dangling nearby and toughed the bulb near the base. Because the bulb is on a 240 cct, the base screw base was live. The dangling chain was bonded to ground at somepoint and he said that sparks were flying. There were sparks at a nearby plug aswell and the breaker didn't trip. My question is why didn't the breaker trip? Also, the plug was fed through EMT without a bonding conductor. Is it possible that the locknut of the connecter was loose and not giving a sufficient enough ground to trip the breaker? Is it possible that the ballast is wired up in a way that the cct isn't protected by the breaker? I'm totally stumped. Any thoughts would be great. Also, with HPS ballasts, will I have the high starting voltage on one of the lines when no bulb is in the socket? If this is the case it explains why my meter is fried now. thanks. Sid |